What ‘The Martian’ can teach us about the weather on Mars

The most gripping aspect of The Martian movie isn’t the space theatrics or the star-studded cast. It’s the background.

If you’ve seen the movie trailer, then you know Matt Damon plays a fictional character named Mark Watney, a NASA astronaut and botanist on a 30-day mission to Mars, who becomes stranded when a fierce dust storm separates him from his crew.

It’s a man-versus-nature tale, and scientists know a good deal about nature on Mars. NASA scientists, equipped with decades of satellite and rover mission data, consulted on the movie’s stunning depictions of weather and geology on the Red Planet.

A scene from The Martian Courtesy of Twentieth Century Fox

Martian author Andy Weir considers those visuals among his favorite parts of the film adaptation.

“You can’t really describe to a reader what a landscape looks like. I mean you can try, but it’s boring. In fact, in my opinion, there’s pretty much nothing less interesting than reading a description of a landscape,” Weir said. “But in the movie, you can really show it. You can say, ‘This is freaking Mars!'”

As I watched Damon/Watney struggle to survive on the desolation of Acidalia Planitia, a 2,000-mile-wide plain on Mars, I was distracted by the wispy clouds floating overhead and the tiny tornadoes swirling behind him.

“We call them dust devils. We see them all the time on various areas on Mars,” said Jim Green, director of planetary science at NASA. “They’re much like water spouts on Earth.The heat from the soils and the atmosphere interact, drawing the dust up and creating a swirl.”

Several dust devils moving from right to left across a plain inside Mars’ Gusev Crater. Photo by NASA’s Mars Exploration Rover Spirit

A towering dust devil on the Martian surface captured by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. This dust plume is more than half a mile in height and about 30 yards in diameter. Photo by NASA/JPL-Caltech/University of Arizona

Green says these winds have been unintentional helpers in NASA’s rover missions. When they landed more than 10 years ago, the Spirit and Opportunity rovers were designed to last 90 days, because it was predicted that dust would settle on their solar panels.

“But what’s happened is the dust devils sweep the the panels. They’re both in a really nice area with plenty of dust devils.They just charge back up and off they go,” Green said. Opportunity has been kept clean by dust devils for the last 11 years. (Spirit got stuck in a sand trap in 2009, and eventually ran out of power.)

Early in its mission, the Spirit was hit by another aspect of weather featured in The Martian: a gigantic dust storm. These storms feature in the book and movie too, though in this case, the narrative takes some dramatic liberties with the science.

“In reality, a Martian dust storm wouldn’t have enough force to do anything. It could barely knock over a piece of paper because Mars has an extremely thin atmosphere,” Weir said. The winds can be as fast as 120 miles per hour, but the pressure is so low that it isn’t enough to straighten an American flag, according to Green.

Still, the dust storms are somewhat terrifying.

This artists concept illustrates a Martian dust storm, which might also crackle with electricity. Photo by NASA

“The dust storms in reality can look as mean as the one in the movie. We’ve seen that from orbit,” Green said. “It’s talcum powder-like dust can reach 30 kilometers [19 miles] in height. It’s a really huge formidable walls of dust coming at you, and when it sweeps over, it just takes out the light.”

Another shocking feature is the lightning. As these dust storms pass by, we can actually see lightning strikes, Green said. But the color of these flashes might be slightly different from what we see on Earth, since the composition of the Martian atmosphere differs from ours.

“They’ll be a combination of what we would normally see as regular lightning and some elements that would be respective of the material that it’s passing through,” Green said.

“In one part of the movie, [the character] Beth Johanssen says, ‘We’re getting a weather forecast, and it’s worse than we predicted earlier.’ That’s exactly right. Windspeed, temperature, all that stuff — we can predict based on real data,” Green said. “On Mars today, we are about where NASA and NOAA were in the 1970s in terms of predicting weather and climate.”

Is Mars the next best home for humanity?

Matt Damon as astronaut Mark Watney who faces seemingly insurmountable odds as he tries to subsist on hostile Mars. Courtesy of Twentieth Century Fox

I asked both Weir and Green to weigh in on the colonization question. Suppose humans wanted to colonize outside of Mars — where in the Solar System should we go?

Venus would be one option, Weir said, though you couldn’t survive on the surface. The atmospheric pressure on Venus’ surface is nearly 90 times that of Earth, akin to swimming next to a submarine half a mile underwater. You’d be crushed. Plus, the temperature is almost 900 degrees Fahrenheit, so you’d be fried.

“But the most habitable location in our Solar System outside of Earth happens to be on Venus about [30 miles] off the surface. The air pressure is 1 atmosphere [matching Earth’s surface], and the temperature is about 100 degrees Fahrenheit,” Weir said. “If you were on an outdoor platform or blimp, you would basically need some goggles and scuba gear, but otherwise, you could stand outside in shorts and a T-shirt…on another planet!!”

In the opposite direction of Venus, people have suggested colonies for Jupiter’s moon Europa and Saturn’s moon Enceladus, since both may possess huge subterranean oceans.

“Anywhere you have water in any form, whether liquid or ice, that’s a tremendous boon to any potential future colonization. But not because humans need water [to live],” Weir said. If you were living in a biosphere, which you’d have to do if colonizing a planet like Venus or Mars, and you had the right water purification technology, you could recycle enough water to survive simply by extracting fluids from your waste and the air you exhale. Such technology is already being used on the International Space Station.

“What’s really awesome about water on a planet is you can make rocket fuel very easily,” Weir said. “You can use electrolysis to separate the hydrogen and oxygen, and then you can burn them together, which is the most efficient chemical propellant.”

This pit in the Moon’s Marius Hills is big enough to fit the White House completely inside. Photo by NASA/Arizona State University

The city of Philadelphia is shown inside a theoretical lunar lava tube. Earlier this year, researchers from Purdue University explored whether lava tubes more than 1 kilometer wide could remain structurally stable on the moon. Photo by Purdue University/courtesy of David Blair

“Those lava tubes would be a great place, because the surrounding geology would protect you from radiation,” Weir said. “It would also regulate the temperature extremes. The moon gets very hot during the day and very cold at night. But inside the lava tube, it would maintain a very constant temperature.”

To be fair, a human hive on Venus or these moons would all require one thing: a massive amount of futuristic technology.

Consider the resources there. “We can extract oxygen out of the atmosphere. We can extract oxygen and hydrogen out of the water,” Green said. “Underneath a carbon dioxide ice layer, there’s a significant amount of water ice in the polar cap. In addition, the recent discovery [of flowing water] indicates that there is a fair amount of water either in the atmosphere and/or in underground aquifers.”

The saltiness of flowing streams announced on Monday might make this water source as toxic as a Superfund site, but Green said water in an underground aquifer might be cleaner.

No matter the target, a human colony outside of Earth is likely inevitable, Weir said.

“I know that it sounds weird, but it’s the bootstrapping thing that humans do. Humans will go expand and live anywhere. That’s proven just by our history,” he said. “People live in Antarctica. People live in the Sahara. People live out in the ocean. Humans have a natural instinct to expand.”